Treatment of disease, pain and medical disorders using drugs and/or ionizing radiation (e.g., pharmacotherapy) may be more effective and may have fewer or less severe side-effects when that available of the drug/radiation treatment to a targeted tissue (for example a tumor or other diseased area of the body) is enhanced and/or where availability of the drug/radiation to non-targeted tissue is minimized. For example, radiation therapy and stereotactic radio surgery may be made more effective and less damaging to non-targeted tissues if targeted tissues such as tumors are radio sensitized prior to treatment, or when surrounding non-targeted tissue are radio protected.
The availability of a pharmaceutical to a given tissue in the body is determined by several factors including the concentration of the drug in the systemic circulation, plasma protein binding, the solubility of the drug within that organ, histological/anatomical barriers, the size of the tissue, and the blood flow or perfusion of that tissue. Specifically, the better perfused a tissue, the more drug is brought to a tissue per unit time. (e.g., Brunto et al, Moskowitz et al).
The sensitivity of a given tissue in the body to the effects of ionizing radiation is determined by several factors including the rate of cellular division, the state of differentiation of the cells, the degree of nourishment to those cells including blood perfusion, and the metabolic rate of that tissue (e.g., Rubin and Casarett). Better-nourished tumors are paradoxically more radiosensitive than those that are marginally nourished, although such tissue may also be better capable of carrying out repair to radiation-injured tissue. Most importantly, the higher the metabolic rate of a tissue, the more radiosensitive it is (Ueno 1971, Kimeldorf et al 1950, Smith et al 1951, Blount et al 1949, Rubin et al 1968).
Magnetic stimulation is a known method by which the perfusion of and the metabolic rate of targeted tissue may be alternatively increased or decreased (Zheng et al, Li et al, George et al, Speer et al).
The methods and systems described herein apply targeted magnetic stimulation to change the perfusion and metabolic rate of tissue, thereby making selected tissue more susceptible to the effects of a drug or ionizing radiation, and for making non-targeted tissue less susceptible to such effects.
References that my help provide context and background include, and may be referred to as indicated above include:
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